**HHC 2016 Highlights**

When: September 17 and 18, 2016

Where: Fort
Collins, CO

If you are a
fan of Hewlett Packard calculators and math, the annual HHC conferences, held
every September, could be a weekend conference for you. I have attended HHC conferences since 2003
and went most years.

Here some
highlights from this years’ conference.
You can access the presentations here:
http://hhuc.us/2016/files/Speakers/.
Also with each section, the youtube of each talk is now available as of
today (

**Thank you Eric Rechlin of hpcalc.org**!)**First Day: September 17, 2016**

HP
Calculator Power Supplies: Jim Johnson

For batteries
to work for calculating devices, the batteries must provide power to last (at
least a few months of use), comply with all the regulations (FCC, etc), fit in
a small space, and if the batteries are rechargeable, they must be able to
recharge safely. The area of where
batteries can be used safely is small.
For lithium ion batteries, the range is between 2 and 4 volts, operating
between 0°C and 100°C. Battery problems
caused Samsung Galaxy 7 phone and hover boards to be recalled.

The original HP
35 (1972) power supply worked with 4 different voltages. A similar power supply used for the HP 29C
(1977). As we can imagine, as
calculators grow complex, so do their power supply structures. For the current HP Prime, the power supply
works with 10 different voltages.

From
the HP-35 to HP 9825: Don Morris

We are
appreciative of Don Morris, who was one of the engineers who worked with the HP
35 and HP 9825.

To recall the
HP 35 story, idea of the HP 35 was Bill Hewett’s desire to have a pocket
version of the HP 9100. There were two
plants, Palo Alto, CA and Loveland, CO, involved with the project. A desktop prototype was worked on in Loveland,
where the hand held was developed in Palo Alto.
Hewett set the price of the HP 35 at $395.

After the HP
35, the HP 9805A, and their successors HP 45 and HP 46 were in production,
there were reports HP 9805A had power problems.
Morris found a bug that caused the HP 9805A did not always powered on,
the cause was a C&T chip. The
company fixed the machines but quietly.

Morris also was
involved with the HP 9825A, along with Barney Oliver and Dorian Shainin. The HP 9825A was different from the 35, 45,
and 46: it wasn’t RPN but algebraic
(equations were evaluated as they were written, with implicit multiplication
allowed for one-letter upper case variables).

Morris was
involved with a problem with 9825A. A
scientists in Australia was using the 9825 as part of a high altitude
experiment. A fuse went out, and in
consultation, Morris suggested a ten ampere fuse, which was normally not
recommended for 9825A. Thankfully the
suggestion worked.

Calculator
Bibliography Update: Felix Gross

Gross is
currently putting together a list of calculator documents. As of 2016, the list of entries grew to
4,032, and Gross is asking for references, specifically on the subject of
teaching, electrical engineering, civil engineering, and finance. His email is felix.gross@alumni.ethz.ch .
Gross has noted the publishing of calculator peaked around 1980 and
1981.

Raspberry
PI Update: Jackie Woldering

The Raspberry
PI, a low cost computer which runs on Linux, has taken off. Current models include Model A+, Model B, and
Raspberry Pi Zero. The base model is the
Raspberry Pi Zero, it has mini-HDMI port, one micro USB port, and is used
either a stand-alone or used for embedded design. The Zero model has 1 GHz single-core
processor with 512 MB RAM, and is currently sold for $5.

As I will
mention later, I won a model Zero as a door prize and look forward to learning
about Linux.

The most
advanced model is the Raspberry Pi 3 Model B, which features a 1.2 GHz 64-bit
quad-core ARM processor, wireless port, 1 GB RAM, 4 USB ports, Bluetooth, and
Wifi. This can be yours for $35.

Software
includes Python, Sonic Pi, a music software, and games.

Website: https://www.raspberrypi.org/

Calculation
Tricks: Namir Shammas

We are always
looking for ways to cut computing time down while keeping (or even approving)
computational accuracy. Namir Shammas is
an expert in calculator programming and computation. Here are some of the tips shared:

Calculating
Derivatives: You can adjust the step
size, h, automatically (instead of asking for the user to input h) by using the
following adjustment: h = 0.01*(1 +
|x|).

Newton’s
Method: Avoid dividing by zero in your
steps by replacing the recurring step with:

x_n+1 = x_n * (
f(x_n) * f’(x_n) ) / ( f’(x_n)^2 + E ),
where E is an arbitrary small number that you provide.

Primes can be
found by using the Solovay-Strassen Primality Test and Miller-Rabin Primality
Test.

You can
normalize regression data (reign in data with large ranges) to the range [a, b]
by the following formula:

( (x – x_min) /
(x_max – x_min) ) * (b – a) + a

The user can
choose the values of a and b. Namir
suggests that a = 1 and b = 2. Calculate
regression. Don’t forget to translate
back to the appropriate values.

Next
Generation Calculation Measurement: Richard Nelson

Key factors in
measuring calculator power include current drain of the power, the required
power to operate a calculator, how to troubleshoot component, and how the power
confirm to specs. Nelson demonstrated a
power measurement with a Mooshimeter.
The Mooshimeter is a compact meter that measures voltage, current,
resistance, and temperature. The kicker
is that the Mooshimeter does not have a display, thus it would have to
connected to a computer in order to read results.

HP
41CL Update: Gene Wright

An ultimate
version of the HP 41C is the HP 41CL.
The HP 41CL contains nearly all the functions of the HP 41C, its
available ROMs (except the time module), with other extended commands and
functions. Most HP 41Cs can be turned
into a HP 41CL by replacing its original CPU board. Talk about expanding the life of the HP 41C,
which first came into our calculator community in 1979.

Should you have
one (or buy one, which will cost you about $250), there are new updates for the
HP 41CL, such as:

PowerCL
Extreme: additional alpha functions
(MID$, LADEL, CLA? (clear alpha?)), flag toggle functions, set and clear flags
indirectly (SFX, CFX)

Total Rekall: Stack shuffle commands and other stack
selection commands

CL Expanded
Memory Rom: has the stack swap functions
from Total Rekall plus room to run four “copies” of the 41C on the same device

Greg J
McClure’s Rom: additional math
utilities, probability distributions, and slide rule functions

HP 67/97 Games
Rom: Most of the games that were
programmed for the HP 67 and HP 97.

The HP 41CL web
page: http://www.systemyde.com/hp41/index.html

HP-41CL
ROM Database: Syvlain Cote

Cote
demonstrates updating a HP 41CL. The ROM
can be updated one image at time, or all eight pages at once.

3D
Printing and Machine with the HP Prime:
Jim Donnelly

Donnelly
dedicated his talk to Don Morris. I am a
fan of 3D printers and amazed of what they produce. Donnelly express that the HP Prime should be
able to not only express 3D graphs but also generate 3D printer files that will
be used as programs used in the printer.

There are two
printing files: CNC and STL. CNC files
describes how the cutting tools act, while STL files describe what is to be
printed. Challenges include the natural
files and limits of what can be stored in strings and lists.

Donnelly
created several HP Prime programs to assist the printer in creating CNC files
(ReadPrimeList, WriteColumnUp) and STL files (MAKEVERTEX, FMT).

Merely talking
about it just doesn’t do it justice, to see the programs and results, please
see the presentation (by Jim Donnelly) in the HHC 2016 link provided at the
beginning of this blog entry or the video above.

New
RPL: Gunter Schnick

The HP 50g may
no longer be in production (production has ceased in 2015), but that doesn’t
stop us enthusiasts from programming and improving on the 50g
infrastructure.

Some features
of New RPL (which is still a work in progress, according to the website, it is
about 25%):

* Increase in
speed processing, from 4.6 times faster (than a normal HP 50g) for complex
functions to 60 times faster for basic arithmetic.

* In list
processing the functions of [ + ] and ADD are reversed from the HP 50g
practice.

* There are six
more soft keys, mapped to the [APPS], [MODE]. [TOOL], [VAR], [STO>], and
[NXT] keys. Affected functions are moved
elsewhere. For example, Undo is moved to
the left key, copying and pasting modes are also mapped to the left key (by use
in combination with the left-shift key), and the [HIST] key now house store and
recall.

* Pressing and
holding [ ON ] with [SPC] toggles with format setting (STD, FIX, SCI,
ENG). Holding [ON[ with a number key
gives the decimal place setting.

* Numbers in
NewRPL can have exponents up to 3000 instead of just 499.

* With the
degree and radian tags, the grads and DMS (degree minutes second) angle tags
have been added.

**Second Day: September 18, 2016**

DM
42: Gunter Schnick

Swiss Micros (www.swissmicros.com) is known for creating credit card size
(and for some, larger landscape) versions of the HP 11C (DM 11), 12C (DM 12),
41C (DM 41), 15C (DM 15), and 16C (DM 16).
In the works is a recreation of the HP 42S currently named the DM
42P. While still smaller than the HP
42S, the DM 42P would be an enhanced 42S.
Improvements include a USB port, a clock, SD slot (backup), 128KM RAM, 5
MB flash, and alpha keys moved to the keypad.
The proposed screen would become larger, from 2 lines to 6 lines, one will
be used for the soft menu. The DM 42
will run on Thomas Oakken’s Free42. Swiss Micros plans to release the DM 42S in
late 2016 (it could be possible the official release takes place in 2017).

This video from
Michael Steinmann of Swiss Micros shows a rendering of what the DM 42P will
look like: https://www.youtube.com/watch?v=qxZQQkh_8Og&feature=youtu.be

Even
More RAM with FRAM71B: Bob Prosperi

The HP 71B
keeps getting new life. As the slogan
“Now you can cram even more RAM, with FRAM”, the FRAM71B upgrades the memory to
a base 512 KB (which can be doubled), allow two “copies” of the 71B to work in
the same machine, lowers the power consumption in sleep mode, and adds the
FORTH/Assembler and HP-41 Translator ROMs.
Propsperi details the development of the FRAM71B and how the software
would be installed with into the HP 71B.

The new FRAM71B
boards are limited in availability, see this thread for details for availability
and cost: http://hpmuseum.org/forum/thread-5437.html

HP-01
“Cricket”: Geoff Quickfall

In addition to
being an air pilot, Quickfall is the go-to man when it comes to restoring and
repairing classic technology. Quickfall
talks about repairing the class HP-01 watch and installing a repair kit,
created by Berhard Emese. The repair not
restores the watch but gives additional features: extended battery life and two hundred year
calendar range (1900-2099).

The talk
concludes with the HP 25E/19E ACTs, which updates any HP Woodstock series
calculators (1970s).

Final
comment: I have got to believe that
wearing a HP-01 in the late 1970s made you the hit of the discotheques.

HP
71B Compendium: Sylvain Cote

Cote’s compendium
lists all the documents associated with the HP 71B (including mods, product
ROMs, overlays, manuals, etc).

It is being
updated, but here is a link to the 2015 compendium: http://www.hpmuseum.org/forum/thread-5286.html

HP
Prime Regression Model Selection: Namir
Shammas

The talk was
dedicated to Jon Johnson, who was the curator of the HP Computer Museum website
(http://hpmuseum.net/). Rest in peace, Johnson.

The best fit
programs is based on the best fit linearized programs for the HP 65, HP 67, and
the PPC ROM.

Generally, two
data sets are used, one called a training set and one for a data set, with each
set having different noise (unexplained variations). For
each model tested, the following are calculated: slope, intercept, and the MSSE (mean square
sum of errors) for both the training and data set along with a weighted
average. From the calculations, the
model with the best fit is selected. The
programs featured at Best_YX_LR_Machine_Learning_1.txt and Best_YX_LR_Machine_Learning_2.txt,
the latter used normalized values.

For details and
programming, please check out Shammas’ talk about curve fitting (see the link to
the talks about the beginning of this blog entry).

In
Praise of the SR-56 Calculator: Gene
Wright

This talk is a
comparison of the Texas Instruments SR-56 (1976) and the HP-25 (C) calculators.

Regarding the
SR-56 and HP-25:

* The SR-56 had
100 partially merged steps (steps only merged with the [2

^{nd}] key). The HP 25C only had 49 steps, but they were fully merged (with the [ f ], [ g ], [ STO ], storage arithmetic, and [ RCL ] keys).
* There were 10
data registers available at all times on the SR-56, while the HP-25 only had
eight.

* For
comparisons, the SR-56 used an independent t register, while the HP-25 used the
x and y stacks.

* The SR-56 had
a [2

^{nd}] [LRN] (f(n)) sequence that allowed access to the Î£+, Î£-, mean, standard deviation, and rectangular/polar conversions. This was the only way these functions could be accessed.
* Unique to the
SR-56 were subroutines, DSZ (decrease by 1, skip on 0), and pause. Unique to the HP 25C were a low battery
warning, % key, H to HMS conversion, and engineering mode.

Programming Contests

Every year
there are two programming contests. They
may be over but you can check them out right here:

RPL (HP 48, 49,
50): http://www.hpmuseum.org/forum/thread-6871.html

RPN (WP-34): http://www.hpmuseum.org/forum/thread-6870.html

Door
Prizes

My Haul: Raspberry PI (top), TI-15 (left), HP 49G (center). The HP 50g I already had. |

There was
enough door prizes to go around that everyone left with at least three items
each. I donated an HP-50g (black
keyboard) and a Calculated Industries Real Estate II. I did pretty well for the door prizes: HP 49G (not 49g+, instead the blue keyboard
which to my surprise is really good), TI-15, and a Raspberry Pi Zero (a Linux
computer).

Plans
for HHP 2017

If you get a
chance and you are a fan of calculators (particularly Hewlett Packard), I
encourage you to attend. The next
conference is scheduled to be on September 16-17, 2017, place to be determined. As we get closer to next September, more
details will be worked out.

I want to do a
presentation for the conference, right now one of two topics I am thinking of
are talking about my blog or fast tips and tricks for the HP 12C. Of course, this is all subject to change.

Until next
time, have a great and wonderful day,

Eddie

This blog is
property of Edward Shore, 2016